At random times, magento sends order emails to random customers who had nothing to do with that order. The order placed by the customer id 1 for example can get also sent to the customer with id 20 and/or id 12 without any particular criterion being applied or any reason for it.

I do not know of the problem and so my question is rather vague, but the conclusion of an order magento correctly sends the confirmation reception order, but sends it to casual users registered on the site. What are the files that manage the sending of these emails?